US2950540A - Willow driers - Google Patents

Description

G. FLESSNER WILLOW DRIERS ug. 3U, 19150 2 Sheets-Sheet 1 Filed Sept. 24, 1956 ,mn/. M MM, w

ug. 3U, 1960 G. FLEISSNER 2,950,540

WILLOW DRIERS me@ sept. 24, 195s 2 sheets-sheet 2 mmh BY 6M# WM ma@ ATTORNEYS WILLW DRIERS Gerold Fleissner, Egelsbach, near Frankfurt, Main, Germany, assigner to Fleissner & Sohn Maschinenfabrik, Egelsbach, near Frankfurt, Main, Germany, a rm of Germany Filed Sept. 24, 1956, Ser. No. 611,658

Claims priority, application Germany Sept. 28, 1955 Claims. (Cl. 34115) The present invention relates to'new improvements in willow or sieve drum driers for drying loose brous material.

ln driers of this type such as were known prior to this invention, the brous material or ber bat was usually moved along a revolving sieve drum by being coiled partly over and partly under the upper and lower halves of the drums, respectively. Such movement of the material along the lower halves of the drums required considerable force in the form of suction merely for the purpose of holding the material attached to the drum Surface. Therefore, since the suction required for the drying operation was also used for retaining the brous material on the lower drum surfaces, it was unavoidable that tufts of bers dropped off these surfaces.

In order to be able to utilize the suction current entirely for the drying operation and to prevent ber tufts from dropping o the drums, the attempt has already been made to rdry the loose brous material merely on the upper sides of a series of perforated drums which are disposed adjacent each other and all rotate in the same direction. However, in carrying out such method, diiculties have been encountered in transferring the bat of loose brous material from one drum to the upper surface of the other. The bat was only partly picked up from the previous drum or it rolled together between the adjacent drums so that the following drum could only receive a part of it. Consequently, the material was likewise conveyed over the drums unevenly and could also not be dried uniformly.

It is therefore the principal object of the present invention to convey the bat of loose fibrous material uniformly along the upper surfaces of a series of perforated drums and to prevent the material from sticking to the individual drums, from being rolled up between adjacent drums, or from partly dropping off the drums.

A feature of the invention for attaining this object consists in providing a plurality of adjacent perforated drums which are rotated in the same direction and over the upper sides of which the bat of brous material is passed, and mounting a hollow perforated roller intermediate each pair of adjacent drums so as to rest and roll preferably under its own weight on the upper surface of the bat, so that the latter will be continuously in contact with and guided by the surfaces of either the surfaces of the drums or those of the intermediate rollers.

An additional advantage attained by the invention is the fact that the drying chamber in which the perforated suction drums are mounted may be of much lower height than required previously in previous driers of this type. This is due to the fact that heating elements are only required inthe upper portion of the drying chamber. This advantage may be further utilized according to the invention by providing two or more rows of drums underneath each other so that the eiciency of the entire drier will at least be doubled and the outer dimensions thereof be considerably reduced.

nited States Patent Further objects, features, and advantages of the present invention will be apparent from the following detailed description which is to be read with reference to the accompanying diagrammatical drawings, in which- Fig. l shows a willow drier according to the invention with a single row of perforated drums;

Fig. 2 shows a similar drier with two rows of perforated drums superimposed upon each other;

v Fig. 3 shows a detail view of a portion of two adjacent drums with the intermediate perforated roller, illustrat- Y ing its action upon the bat of bers; and

t suction fans.

Fig. 4 is a cross-sectional view through Fig. 2 and showing the suction through the bat and drums.

Referring to the drawings, and rst particularly to Figs. l and 3, the new drier consists of a housing 10 in which a plurality of perforated drums 11, 12, 13, and 14 are rotatably mounted. A pair of conveyor belts 15 and 16 conduct the bat 20 of loose fibrous material toward and away from the drums and the drier. Hollow perforated rollers 17, 18, and 19 are interposed between the adjacent drums 11, 12, 13, and 14, respectively, and rest with their own weight on the bat 20 and the respective adjacent drums. Cover plates 21, 22, 23, and 24 are provided in the customary manner at the inside of the drums so as to cover up those parts ofthe drums from the inside thereof which are not covered on the outside by the ber bat 20. Thus, as shown in Fig. 3, the bat 20 runs over that part of drum 11 which is not covered on the inside by the cover plate 21, and it is attached thereto due to the suction of the The upper end of cover plate 21 is disposed relative to the perforated roller 17 so that there will be no suction upon bat 20 intermediate the two ldrums 11 and 12 so that the bat will then be released from drum 11 and be picked up by or follow the perforated roller 17 because of the fan suction which then again canv exert its action. The same procedure is repeated at the perforated rollers 18 and 19 until the ber bat 20 is nally taken olf the surface of drum 14 by the 'conveyor belt 16.

In this movement of ber bat 20 along the surface of drums 11, 12, 13, and 14, the perforated rollers 17, 18, and 19 also rotate, being driven merely by the friction on drums 11 to 14 or the ber bat Z0, respectively. These rollers also pull the ber bat slightly apart without, however, changing the thickness or width thereof on the drums. Since rollers 17, 18, and 19 are perforated, they do not obstruct the free passage of air to the ber bat.

Although the frictional engagement of rollers 17, 18, and 19 on the bat is usually suicient to rotate the same, they may, if desired, also be positively driven by any suitable driving mechanism.

Since a willow drier of a type according to the invention may be enclosed within a very low housing 10, it is also possible to provide two rows of such perforated drums underneath each other and to pass the ber bat rst over one row of drums, for example, the lower row, and thereafter over the other.

Such embodiment of the invention is diagrammatically illustrated in Fig. 2, in which -two rows of `drums 11 to 14 and 25 to 2S are mounted underneath each other, and la perforated roller is mounted between each pair of adjacent drums. The ber bat 26 is inserted into the drier on the lower conveyor belt 15 and runs over the upper sides of ` drums 11, 12, 13, and 14, whereupon it is passed from drum 14 over drum 25 of the upper row and then successively over the other upper drums 26, 27, and 28, and nally out of the ldrier on the upper conveyor belt 16. The air then flows through the drums in a downward direction, as directed by baffles 29, 30, 31 and 32, and -is drawn off the lower drums in the axial j l l 2,950,540

direction thereof. Motors MY rotate the drums, and, if Y" desired, the rollers by means of the gearing and shafting shown :in Figs. 1, 2 and 4, and at the same time drive the suction fans 35V which communicate with the interiors of thevr drums Vfor'v drawing anair current through the rollers, bat and drums for drying the hat.V

Fig. 3 -finally-shows on an enlarged scale the gap inter-V mediate twofadjae'ent' drums whichis iilledout by the perforated'roller'17. Such arrangement of the drums saves considerable Vspace permitting even a larger number of drums to be mountedY Within the smallest possible space, thus increasing thedrying eliiciency of theY drier and 'keeping the cost of production and Yoperation thereof at the lowest 'possible level.

' While the invention has beendescribed in detail and Having thus described my invention, wha-tl claim as new is: v Y

1.7A willow drier `for drying a bat of loose fibrous materialv comprising a plurality of perforated drums mounted Yadjacent each other in the same plane, means for rotating said drums in the same direction and for passing said bat along the upper sidesof said drums,` a

perforatedrroller rotatably mounted above and intermediate each pair of adjacent drums and adapted `to actY VSame plane, means for rotating said drums in the same direction and for passing said bat along the upper sides of said drums, a perforated roller rotatably mounted aboveand in the yV-shaped gap intermediate'each pair of adjacent drums and adapted to rest under its own weight on the upper surface of said bat, baies arranged on vthe lower sides and inside of the said perforated drums and ending adjacent to therlines of contact befv tween said rollers and saidfbat, and suction means communicating with the interiors ofmsaid drums yfor drawing an airfcurrent through said rollers, said bat, and said drums for drying said bat.

3. A willow drier for drying a bat of loose iibrous material comprising a plurality of perforated drums mounted in a row closely adjacent each Vother inthe same plane, meanst'for rotating said drums in the same direction and for passing said bat along the upper sides of said drums, a perforatedV roller rotatably mounted above and in the V-shaped gap intermediate each pair of adjacent drums and adapted to rest under its own weight on the upper surface of said bat, batiies-arranged on the lower sides andinside of the said perforated Y 'drums and'endin'g in the drumsv in advance of said rollers above the lines 'of contact between the said rollers `and said bat and rearwardly of said rollersrunder the lines of contact between the said rollers and said bat, and suction means communicating withV the interiors of said drums lfor drawing an air'current through said rollers,

said bat,-and said drums for drying said bat.

4. A willow drier Lfor drying abat of Vloose Iibrous material comprising a plurality of perforated drums mounted in at least -two superimposed rows and closely Y adjacent each other in the same plane in each respective row, means for rotating said drums in one row in one direction and those in the superimposed row in the opposite direction,V -a perforated roller mounted above and in the V-shaped gap intermediate each pair of adjacent drums Ain eachrow and adapted to act upon the upper surfaceV of said bat, baffles arranged on -t'he lower sides and -inside of the said perforated drums and ending adjacent to the Ilines of contact between the said rollers and said bat, and suction means communicating with the interiorsqof said drums for drawing an air Ycurrent through said rollers, said bat, and said drums for drying said bat. Y j v Y5. A willow drier as defined in claim 1, further comprising means for positively driving said perforated rollers at a peripheral speed substantially in accordance with the peripheral speed of said drums.

References Cited in the tile of this patent UNITED STATES PATENTS 1,377,793 Schwartz May 10, 1921 1,601,332 Whitehead et al Sept. 28, 1926 FOREIGN PATENTS Great Britain May 14, 1925

Images